Self-locking bottle cap



Jan. 21, 1969 E. c. QUACKENBUSH SELF-LOCKING BOTTLE CAP Filed July '7,1967 INVENTOR Edward G Qaac/cenbus/z BY 1,62%, mam M J1. 42

ATTORNEYS United States Patent O Claims ABSTRACT OF THE DISCLOSURE Thedisclosed self-locking closure includes a cap threadably engageableabout the mouth of a bottle. A sleeve surrounds the cap and is connectedthereto by a resilient member accommodating relative axial movementtherebetween. Ratchet teeth formed on the bottom edge of the sleeveengage one or more fixed pawls on the bottle as the sleeve is rotated tothread the cap on the bottle mouth. Rotation of the cap by turning thesleeve in the direction of removal is inhibited unless the sleeve ispulled away from the bottle to disengage the ratchet teeth and pawls.

Background of the invention A variety of safety container closuresdesigned to thwart the removal attempts of children have been proposedin the past. For the most part, such prior art designs have proven .tobe complicated and expensive to manufacture. Indeed, some safety bottlecap designs are found to be so intricate as to render it difficult foreven an adult to eflfect their removal. Other designs require only minormanipulation incident to removal and therefore present no significantobstacle to a determined youngster.

In every household there is an infinite variety of bottle substancesranging from cleaning solutions to insecticides and medicinalpreparations which present a clear and present danger in the hands ofchildren. Each year a number of children die as a result of consumingaspirin tablets alone. Parents endeavor to keep such dangeroussubstances out of the reach of children but children have been known tofind means by which to reach those seemingly unreachable bottledsubstances.

Consequently, there is great need for a safety container closure whichis simple in design and economical to manufacture, and yet is reliablycapable of inhibiting the removal attempts of children. My inventionprovides such a closure. In addition to the safety aspects of myinvention, I also provide an inherent self-locking feature effectivelypreventing spurious unscrewing of my closure as may otherwise occur whenthe container is subjected to prolonged vibrations during shipment,storage, etc.

The invention accordingly comprises an article of manufacture possessingthe features, properties, and the relation of elements which will beexemplified in the article hereinafter described, and the scope of theinvention will be indicated in the claims. I

For a fuller understanding of the nature and objects of the invention,reference should be had to the following detailed description taken inconnection With the accompanying drawing in which:

FIGURE 1 is a perspective view of one self-lock bottle cap embodimentconstructed according to my invention;

FIGURE 2 is a sectional view taken along line 2-2 of FIGURE 1;

FIGURE 3 is a longitudinal sectional view of an alter- Patented Jan. 21,1969 "ice native self-locking bottle cap embodiment constructedaccording to my invention; and

FIGURE 4 is a sectional view taken along line 44 of FIGURE 3.

Similar reference numerals refer to corresponding parts throughout theseveral views of the drawing.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to thedrawing, the self-locking bottle closure, generally indicated at 10 inFIGURES 1 and 2, includes a cap, generally indicated at 12. The cap 12is formed having cylindrical sidewall 14 and a solid top 16 (FIGURE 2).Threads 18 formed in the interior surface of the cap sidewall 14 engagecorresponding screw threads 20 formed in the exterior surface of a neck22 of a bottle, generally indicated at 24, when cap 12 seals bottlemouth 25.

An outer sleeve 26 disposed concentrically about and extendingsubstantially coextensively with the cap 12 is integrally joined to thecap by a resilient spring member, generally indicated at 28. The springmember 28 is integrally formed with the outer sleeve 26 and the cap 12and extends annularly about the top of the self-locking closure 10. Asbest seen in FIGURE 2, the spring member 28 is U-shaped incross-section. Diametrically opposed notches 30 are formed in the springmember 28 to accommodate fiexure of the spring member incident tomanipulation of the self-locking closure 10 in a manner to be described.The number of notches 30 is largely determined by the size of closure10.

The bottom edge of the sleeve 26 is formed into an annular array ofratchet teeth 32 effective to engage fixed pawls 34 upstanding from theannular shoulder 36 of bottle 24 when the closure 10 is applied to thebottle. The number of pawls 34 is largely a matter of choice.

In applying the self-locking closure 10 to bottle 24, sleeve 26 isgrasped and rotated to thread cap 12 on the bottle neck 20. Rotationalmovement of the sleeve 26 is communicated to cap 12 through the springmember 28. As the cap 12 advances down on the bottle neck 22, ratchetteeth 32 come into contact with the fixed pawls 34. By virtue of thephysical geometry of the ratchet teeth 32, continued rotation of theself-locking cap 10 in the clockwise direction (FIGURE 1) is permittedas the ratchet teeth ratchet over fixed pawls 34, As teeth 32 ratchetover pawls 34, the spring member 28 deflects as shown in phantom inFIGURE 2. Ultimately, the mouth 25 of bottle 24 is sealed off againstthe top wall 16 of cap 12.

It is seen that once the self-locking closure 10 is applied to thebottle 24, attempted rotation in a removal or counter-clockwisedirection is inhibited by the abutment of the fixed pawls 34 against thestraight sides 32a of ratchet teeth 32; the ratchet teeth being normallybiased into interengagement by spring member 28. In order to disengagethe ratchet teeth 32 from pawls 34, the outer sleeve must be pulledupwardly away from bottle 24, as shown in FIGURE 1. The resulting axialmovement of sleeve 26 relative to cap 12, fixed in axial position onbottle neck 22, is accommodated by the fiexure of spring member 28generally in the manner shown in phantom in FIGURE 2. At the same timeas outer sleeve 26 is pulled away from the bottle 24 to disengage theratchet teeth 32 from the pawls 34, the sleeve must also be rotated toeffect its removal. If this pulling force is relaxed prior to completeremoval of the closure 10, spring member 28 will revert to its normalcondition causing the sleeve 26 to move axially toward bottle 24 withthe ratchet teeth 32 again engaging fixed pawls 34. It is thus seen,that the axially pulling force on the sleeve 26 must be maintained untilthe cap 12 has been substantially fully screwed off bottle neck 22.

For ease of operation of the self-locking closure 10, it is preferredthat the physical relationship of the pawls 34, ratchet teeth 32 and cap12 be such that the cap threadingly engages the bottle neck 22 beforethe ratchet teeth engage the pawls. In this manner, the sleeve 26 needonly be rotated in applying the closure 10 to the bottle 24; the pawls34 camming over sloping sides 32b of ratchet teeth 32. During removalhowever, composite forces in the form of an axial pulling force and arotational force must be applied to the sleeve 26, a manipulationdifficult for small children. Apart from the safety aspects, it is seenthat mechanical vibrations cannot work closure 10 loose; it beingpositively locked on bottle neck 22.

The closure 10 of FIGURES 1 and 2 is preferably formed in a one-stepmolding operation, requiring no subsequent cutting of forming. Thus,these closures can be readily manufactured inexpensively. The materialof closure 10 may be any suitable semi-rigid thermoplastic such aspolypropylene.

The self-locking bottle closure '10 shown in FIGURES 3 and 4 is formedin two parts of suitably semirigid plastic such as polypropylene, ratherthan integrally as is closure 10 of FIGURES 1 and 2. One part is a cap12' having a cylindrical sidewall 14' and a solid top 16. Screw threads18 on the cap 12 are engageable with threads 20 formed about the neck 22of bottle 24.

The other part consists of an outer sleeve 26' and a resilient springmember 28 integral with the sleeve side. The spring member 28 is in theform of a disk overlying the top 16' of cap 12. A stud 3i, integrallyformed with top '16 extends through a central aperture 29 in springmember 28. The upper end of stud 31 has an enlarged head 33 retainingthe two parts in assembly.

As best seen in FIGURE 4, a series of axially extending splines 35spaced circumferentially about the outer surface of cap sidewall 14engage correspondingly spaced grooves 37 formed in the interior surfaceof sleeve 26. It is thus seen that by virtue of the splines 35 andgrooves 37 rotation of sleeve 26' imparts rotational motion to the cap12 and yet the sleeve may move axially relative to the cap. Thisrelative axial movement of the sleeve 26 and cap 12' is accommodated bythe spring member 28. Ratchet teeth 32' formed in the bottom edge ofsleeve 26 engage fixed pawls 34 on bottle 24.

From the foregoing description, it is seen that the selflocking bottleclosure 10' of FIGURES 3 and 4 is operated in the same manner as closure10 of FIGURES 1 and 2. In fact, the two embodiments are interchangeableon the same bottle 24. As closure 10 is threaded on bottle neck 22, theratchet teeth 32' carried by sleeve 26' ratchet over fixed pawls 34 onbottle 24; relative axial movement of the sleeve 26' and cap 12' beingaccommodated by fiexure of the spring member 28 as seen in phantom inFIGURE 3. Once closure 10 is screwed on bottle neck 22, inter-engagementof the ratchet teeth 32' with the fixed pawls 34 prevent removal unlessand until sleeve 26 is pulled away from the bottle 24 to effectdisengagement. This being done, the sleeve 26 may be rotated; itsrotational movement being communicated to cap '12 by the engagement ofsplines 35 in grooves 37 incident to removal of closure 10'.

It will be appreciated that the bottle 24 may carry the ratchet teeth32, 32 and the sleeves 26, 26' carry one or more pawls 34 withoutdeparting from the invention.

It will thus be seen that the objects set forth above, among those madeapparent from the preceding description, are eificiently attained and,since certain changes may be made in the above article without departingfrom the scope of the invention, it is intended that all mattercontained in the above description or shown in the accompanying drawingshall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended tocover all of the generic and specific features of the invention hereindescribed, and all statements of the scope of the invention, which, as amatter of language, might be said to fall therebetween.

Having described my invention, what I claim as new and desire to secureby Letters Patent is:

1. A self-locking closure for containers, said closure comprising, incombination:

(A) a cap for the container;

(B) means carried by said cap engaging corresponding means adjacent thecontainer top,

(1) said means being effective upon relative rotation of the containerand said cap in a first direction to translate the latter in a firstdirection to a closure position relative to the container top;

(C) an outer sleeve surrounding said cap;

(D) at least one first projection extending from one end of said sleeve;

(E) at least one second projection on the container adjacent its top;and

(F) means interconnecting said cap and said sleeve for couplingrotational motion therebetween, said interconnecting means including 1)a resilient member (a) biasing said sleeve into a position normallymaintaining interengagement between said first and second projectionswith said cap in said closure position such as to constrain relativerotation of the container and said cap in a second direction, and

(b) deflecting to accommodate movement of said sleeve in a directiondisengaging said first and second projections to permit relativerotation of said cap and container in said second rotational directionincident to removal of said closure 2. The closure defined in claim 1wherein:

(1) one of said first and second projections is formed having aninclined side and a straight side,

(2) whereby said first and second projections, by virtue of thedeflection of said resilient member, ride past each other on saidinclined side upon said relative rotation in said first direction andsaid first and second projections abut each other along said straightside to constrain said relative rotation in said second direction.

3. The closure defined in claim 1 wherein:

(1) one of said first and second projections is at least one fixed pawland the other a series of ratchet teeth.

4. The closure defined in claim 1 wherein:

(1) said cap, said sleeve and said interconnecting means are integrallyformed.

5. The closure defined in claim 4 wherein:

(1) said resilient member is U-shaped in cross-section with one edgeintegrally joined with the other end of said sleeve and the other edgeintegrally joined with said cap.

6. The closure defined in claim 5 wherein:

(1) said resilient member is notched to accommodateits deflection.

7. The closure defined in claim 1 wherein said interconnecting meansincludes:

(1) interconnecting splines and grooves formed on said cap and saidsleeve for coupling rotational motion therebetween while accommodatingrelative axial movement therebetween with deflection of said resilientmember.

8. The closure defined in claim 7 wherein:

(1) said resilient member is in the form of a disk joined along itsouter edge to the other end of said sleeve and centrally mounted on apost afiixed to said cap,

(i) said post being received in a central aperture in said disk andbeing enlarged at its free end to retain said disk thereon.

9. The closure defined in claim 7 wherein:

(1) one of said first and second projections is formed having aninclined side and a straight side,

(2) whereby said first and second projections, by virtue of thedeflection of said resilient member, ride past each other on saidinclined side upon said relative rotation in said first direction andsaid first and second projections abut each other along said straightReferences Cited UNITED STATES PATENTS Everett 2159 Towns 2159 Whiteman215-9 Powers 215-9 WILLIAM T. DIXSON, JR., Primary Examiner.

